Various technologies for monitoring the state of a predetermined area have been developed. For example, Japanese Laid-Open Patent Publication No. 2006-208000 (PATENT LITERATURE 1) discloses the following technology. That is, the airflow distribution apparatus for usage in a data center comprises: at least one airflow sensor coupled to a plurality of fans in at least one server in the data center; and a controller coupled to the at least one airflow sensor and configured to monitor airflow for the plurality of fans and control cooling in the data center in accordance with the sensed airflow.